Piston-valve



(Model.)`

W; FOLEY.

PISTON VALVE.

Patented Jam.Y 17,1882.

a AM; m l wuiI/Jvllwllnl mgm v UNITED STATES WILLIAM FOLEY, OE KEOIIUK, IOWA.

PATENT UFFICE PISTON-VALVE.

ASPECIFICATION formingpart of Letters Patent No. 252,449, dated January 1'7, 1882,

Application filed October 15,1880. (Model.)

ing with a round or cylindrical piston-head a steam-chest formed with openin gs at bottom extending up the sides, as' hereinafter described.V

My improvement consists, further, in a valve-stem having a T-head adapted to it in I a suitable recess formedbetween lugs or shoulders, so as to permit the descent of the valve as it wears and at the same time prevent it turning in the steam-chest.

In Order that my invention may be fully understood, I will proceed to describe it with reference to the accompanying drawings, in

. which- Figure l is a vertical axial section of my improved devicc with the valve in side view, showing a :form applicable to any ordinary locomotive-cylinder. Fig. 2 is a vertical axial section with valve in side view, showi'ngthe improvement applied to a throttle-valve. Fig'. 3 is a vertical transverse section of one ofthe pistons, showing mode of applying packingrings on the line 3 3, Figs.1 and 2. Fig. 4 is anend view of the head on a larger scale, showing mode of connecting the stem. Fig. 5 is a horizontal 'section thereof, on a larger scale, on the line 5 5, Fig. 4.

A is part of a cylinder of a locomotive-engine.

Bis the steam-chest, cylindrical upon its inside.

C is a head made to t the inside of the steam-chest, and consisting of two pistons, c c', with a connecting-neck, c3, and steam-passage c4, extending completely through the head, to connect chambers b and b at each end.`

The head is preferably cast inone piece. Each piston has a circumferential channel to receive the packing-upon it, the rings being held bythe circumferential flanges c5, forming the side walls ot' the channel.

The packing' consists of two rings, d d', forl each piston, each made with a single trans-- verse or oblique cut, so that they are sprung into their channel in such relative [po-ition as to break joint, the rings being sprung` inward as the piston passes into the steam-chest, and tending to spring outward` against the inside of the steam-chest, so that asteam-tightjoint is made between them.

The packing-rings, working in conjunction with the cylinder-ports a. are lnade at. least as wide as said ports, so as to close them in a certain position of the valve. In practiceIh-ave made these rings ot' width suiii-ient to give the required lap, as shown in the drawings, the rings beingmade, say., one-halt' inch (more or less). wider than the cylinder ports a..

.The induction-ports of the steam-chest are shown at t', and the eduction-port ofthe steamchest is shown at e, while the valve-ports of the cylinder A, which; of course, act alternatelyas induction and eduction ports, are shown at a.

b2 is` the exhaust-chamber. y

Within the piston c of the head Gis a recess to receive the T-head fof the valve-stem F.

gg are lugs each side of the recess to engage the prongsot1 the T-head. The arrangement is such that a connection is made between the stem and the valve without any screw or key, and the stem has capacity for vertical movement in the recess as the valve wears upon its seat., lis a stuffing-box, through which the valve-stein passes. When the valve is in the position shown in Fig. l the ports are closed ;l

then when the valve is moved away from the stung-box the steam-chamber ot' the head is brought in conjunction with the port a at that end of the cylinder.

It will be seen that the valve is perfectly balanced as far as end-pressure is concerned, and is nearlyubalanced otherwise, because the pistons tit all around the inside of the steamchest, so that there is no steam-pressure on the upper sides of the pistons, and the steampressure upon the connecting-necks is equal on every side. i

In applying my improvement to old locomotive-engines, or locomotive-engines where the with the end of the rocker-arm.V The operation of this valve is the same as that of an ordinary D-valt'e; but its construction is different therefrom, as before described, it being perfectly balanced except at such times as the pistons of the Valve overlap the edges ofthe steam-ports. In applying the improvement to an old engine the steam-chest B must be, of

course, a separate casting from the cylinder A, but in the application ofvmy improvement to a new engine thel steam-cylinder A and steam-chestB may becast in one piece.

In Fig. 2 my valve is shown as a throttlevalve, the construction of the valve itself being similar to thatshown in Fig. 1. In this application the steam may enter through an intiluctioirport, i', at eitheror both ends ofthe steam-chest, the steam-pressure being equalized in both of the steam-chambers?) b by the steam-passage c, extending through the valve, as indicated by broken lines. When the valve is in the position shown the steam-port a and the exhaust-port e are in communication and shut o' from the steam chambers b b.- If the valve is drawn from this position toward the stut'ting box, the steam-port t is thrown into communication with steam-chambers b, and the piston clclosestheeXhaust-port e, so that steam ows through the port a; into any steam cylinder or chest with which it may be in communication. When the valve is returned to the position shown the steam escapes through port a into the exhaust-chamber Wand through the eduction port e. The valve stem F ot' the throttle-valve may be connected to any suitable operating-lever.

The flanges 0.5 need notbe cast in one piece with their pistons, but may, one or more or all of them, be in separate pieces, and attached to their pistons by screws or otherwise.

I am aware that it is old to construct. a cylindrical steam-chest with three ports at bottom and two inlet-ports at top, and do not, therefore, claim such construction, broadly.

' Having thus described my invention, the following is what Iclaim as new 'therein and desire to secure by Letters Patent:

l. The combination of the round or cylindrical piston-headO, formed ot' two pistons, c c', with aconnecting-neck, c3, having steampassage c4, extending through the neck and pistons, and the steam ychest B, formed with induction-port and openings a e at bottom, eX- tending up the sides of the steam-chest, as set forth.

2. 'The combination of the round or cylindrical piston-head C and the steam-chest B, formed with openings t' i a a e at bottom, and

set forth.

Y 3. The combination ot' the valve-stem F, having T-headf, and piston c, havinglugsgg,

the said stem and head adapted to tit inI asuitable recess formed between lugs or shoulders g g, to permit the free descent ofthe pistonturning in the steam chest.

VILLIAM FOLEY.

Witnesses:

SAML. KNIGHT, C'. H. BROWN.

extending up the sides ot' the steam-chest, as

head as the valve wears and to prevent its f 

